tsütokinins

Cytokinins are a class of plant hormones that promote cell division, also known as cytokinesis. They are primarily involved in plant growth and development, particularly in the regulation of cell division and differentiation. Cytokinins are produced mainly in the root tips and are then transported throughout the plant.

The primary role of cytokinins is to stimulate cell division, which is essential for growth. They work in conjunction with other plant hormones, such as auxins, to control various developmental processes. For instance, the ratio of cytokinins to auxins influences whether a plant develops roots or shoots from undifferentiated cells. A higher cytokinin to auxin ratio generally favors shoot formation, while a lower ratio favors root formation.

Beyond cell division, cytokinins also play roles in delaying leaf senescence, which is the aging process of leaves. By delaying senescence, cytokinins help to maintain the photosynthetic capacity of leaves for a longer period. They are also involved in bud formation, the development of flowers, and fruit development.

Cytokinins are a group of adenine derivatives. The most well-known naturally occurring cytokinins include zeatin, isopentenyladenine (IPA), and kinetin. Synthetic cytokinins are also used in agriculture and horticulture to promote plant growth and improve crop yields. Their applications include tissue culture, where they are used to induce cell division and regeneration of plant tissues.